Reversible hammermill with powerdriven impactor surfaces



Dec. 1, 1953 E H, KEIPER l 2,661,160

REVERSIBLE HAMMERMILL. WITH POWER-DRIVEN IMPACTOR SURFACES Filed 00?.. 26, 1951 Patented Dec. l, i953 I UNITED srArgEs l earENr- OFFICE .Y REVERSIBLE -HAMMsamLL-wrrn Powere-A DnrvaN niederen 'simmons Edwin H. Keiperg ?hiladelphiaia.,.assigner to Pennsylvania Crusher Company, Philadelphia, Pa.,a corporation of New York apelada@ ocaber 26, i951, serial no. 253,409

This invention relates to hammermills of the center feed type and particularly to the breaker surfaces on the sides of the entrance chamber.

rlhe object of the invention is to provide. a center feed hammermill that effectively crushes both dry and wet material.

Another object of the invention is to provide a center feed hammermill with self-cleaning breaker surfaces.

Another object of the invention is to provide a center feed hammermill with breaker surfaces from which sticky material is removed to fall outside of the crushing zone and drop clear of the breaker surfaces.

A still further object is to provide a center feed hammermill with breaker surfaces that maintain themselves clean of wet sticky material and expel the material from the vicinity of the breaker surfaces so as not to interfere with the operation of the machine.

Gther objects and advantages of the invention will appear from the following specification taken in connection with the accompanying drawing in which:

Fig. l is a vertical sectional view of a typical embodiment of the invention;

Fig. 2 is an end View diagrammatically illustrating the drives for the rolls; and

Fig. 3 is a fragmentary View of a roll and scraper.

In Fig. 1 a reversible center feed hammermill symmetrical about a vertical plane through the center of the rotor I0 is shown. The rotor IG has hammers I I fed with material at the top center of the hammer circle from a feed chute I2. E

The material is crushed against the breaker surfaces comprising rotating rolls I3, Iii, I5 and carried down against the screen bars I E and passes out of the crusher through the slots I'i between the bars and the opening 2t.

An outer casing is provided enclosing the rotor along the shaft 28 and pivotally carry the haml mers II. Rows of hammers are thus formed longitudinally of the Crusher between the end plates I8. Material drops through the chute i2 and enters the rotor I0 radially at top center.

The hammers I I fracture the material and drive 2 claims; (ci. ,2n-iss) I itagainst the rolls It,

It, I5. The material is reected from the rolls and rebounds for further reduction between the hammers and rolls. The reduction action then passes down between the hammers and the screenbars I5. The plates 29 at an angle across the discharge opening 2li provide a linal reduction of the material.

The screen bars It are mounted on the supporting beam 3i pivoted at its upper end and having an adjusting mechanism 32 at its lower end. The plates 29 are pivotally supported by pins 33' at their upper ends and adjustably supported by the rods 3d pivotally connected to the lower ends by the flexible joint 35. The opposing anvil plate is drawn back to clear the opening 24. In the case of clockwise rotation the plate on the right side is drawn back and on counterclockwise rotation the plate on thev left side is drawn back.

The rolls I3, It, I5 are mounted on shafts iiD, lil, 42 respectively carried in bearings in the end plates and are driven by gears 43 from the worms lid. In the gear drive shown, drive shaft 28, through worm gear i5 and clutches lit, drives the rolls on the left side counterclockwise and the rolls on the right side clockwise.

The rolls against which the material is being hit must be turning. The other set of rolls are preferably idle.

The rolls I3, I4, I5 are preferably hollow cylinders with radial disks supporting the rolls concentrically on the shafts lit, dI, l2 respectively. The shafts are set so that adjacent rolls may engage one another but are preferably spaced. Although the rolls may be spaced and have separated surfaces the rolls are so spaced that a substantially continuous anvil surface is presented to the material hit by the hammers and the hit material does not pass through the space between the rolls. The roll I5 is positioned so that the anvil surface of the rolls starts below the hammer circle and continues up on the other rolls I3 and Id above the hammer circle on the side of the entrance chamber. The rolls may be in separate longitudinal sections so that worn and unworn sections may be interchanged to distribute the wear and lengthen the life of the rolls.

The rolls I3, I4, I5 form impact or breaking surfaces against which the material is hit. Wet or sticky material forms a coating on theI breaker surfaces reducing the eiciency of the reducing action. The rolls I3, llt, i5 are turned to move the exposed surfaces of the rolls upwardly and present clean surfaces towards the rotor. On the other side of the rolls, .Scrapers 13,8, de, 50 are provided extending longitudinally along the rolls I3, I4, I5 respectively and remove the material from the surface of the rolls. The scrapers may be pivotally mounted at each end on flanges 5|, 52, 53 respectively which are fastened to the end walls IS by bolts 54. Springs 55, 56, 51 are mounted respectively on the flanges 5|, 52, 53 and press against the respective Scrapers to resiliently hold them in engagement with the surface of the rolls. The edge of the scraper removes the adhering material from the surface of the roll. Thel loose material slides over the tops of the Scrapers free of the roll. The spaces along the top surfaces of each blade are preferably free of any obstruction to form a continuous open passage or channel 58 between the wall 20 and' the roller I3, scraper 58, roller l and scraper 49. The' passage 58 continues on down between the wall 2| and the scraper 49 and roller l5 into a chamber 63 in back of the screen bars IB. The material removed by the scraper 48'- from the roll I3 drops into the passage 58 onto roll I4. The material is then scraped off by scraper ISS from the roll- I4 and falls into the passagel IlS. These scrapings combine with the scrapings from the roll |35 and drop into the chamber 63' clear of the crushing mechanism of the hammer mill and thence out through the opening in the bottom of the casing.

The sticky material does noti become adhered to the rolls building up thick layers and is removedv from the mechanism so that it is kept clean and operable during long periods.

I claim:

l. A crusher having` a rotor carrying hammers, a feed chute terminating vertically above the top of the rotor and providing an entrance space through which material is freely dropped vertically downward into the top of the hammer circle of the rotor, a movable anvil means having surfaces along one side of said entrance space and extending from an upper point above the top 0f said hammer circle and at the lower end of said feed chute to a lower point at the downward side of said hammer circle and below the top thereof, driving means for moving said anvil means to carry said surfaces upward over the rotor and upward along the side of said entrance space and tangent to the vertically dropping material in said entrance space to receive the materialthrown by said hammers across said entrance space and across the paths of the material' entering vertically from the feed chute, and scraping means engaging the surface of the anvilV means to remove material adhering thereto. Z. A Crusher as set forth in claim l in which the movable anvil means comprises a plurality of cylindrical rolls.

EDWIN H. IiEIPEI-..

References Cited in the le of this patent UNITED STATES PATENTS Number Name Date 1,049,712 Helbig Jan. 7, 1913 1,930,873 Brewster Oct. 17, 1933 2,471,068 Keiper May 24, 1949 2,523,004 Fowler Sept. 19, 1950 FOREIGN PATENTS Number Country Date 480,808 Germany Aug. 9, 1929 

